Proton number & Nucleon number
Proton number is the number of protons in the nucleus an atom.
Proton number is also known as atomic number.
Nucleon number is the number of protons and the number of neutrons in the nucleus an atom.
Nucleon number is also known as mass number.
Note: From this equation, we can derive another 2 equations to calculate the number of neutrons & the number of protons.
Number of neutrons = nucleon number – number of protons (proton number)
Number of protons (Proton number) = nucleon number – number of neutrons